Method performed by UE, method performed by base station, UE and base station

Abstract

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. The present disclosure relates to a method performed by a UE, a method performed by a base station, the UE and the base station. The present disclosure relates to a 5G communication system or a 6G communication system for supporting higher data rates than 4G communication systems such as Long Term Evolution (LTE). One aspect of the present disclosure provides a method performed by a user equipment UE in a communication system, including: receiving first information, wherein, the first information includes information related to a plurality of resource sets; using a first resource to perform a first grant-free transmission, the first resource belonging to a first resource set among the plurality of resource sets; in case that second information in response to the first grant-free transmission is received and the first grant-free transmission is unsuccessful, determining a second resource used for a retransmission based on the second information, and using the second resource to perform the retransmission, the second resource belonging to a second resource set among the configured resource sets.

Description

METHOD PERFORMED BY UE, METHOD PERFORMED BY BASE STATION, UE AND BASE STATION

[0001] The present application relates to a field of wireless communication technologies, and more particularly, to a method performed by a user equipment (UE), a method performed by a base station, the UE and the base station.

[0002] 5thgeneration (5G) mobile communication technologies define broad frequency bands such that high transmission rates and new services are possible, and can be implemented not only in "Sub 6GHz" bands such as 3.5GHz, but also in "Above 6GHz" bands referred to as mmWave including 28GHz and 39GHz. In addition, it has been considered to implement 6G mobile communication technologies (referred to as Beyond 5G systems) in terahertz bands (for example, 95GHz to 3THz bands) in order to accomplish transmission rates fifty times faster than 5G mobile communication technologies and ultra-low latencies one-tenth of 5G mobile communication technologies.

[0003] At the beginning of the development of 5G mobile communication technologies, in order to support services and to satisfy performance requirements in connection with enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communications (URLLC), and massive Machine-Type Communications (mMTC), there has been ongoing standardization regarding beamforming and massive MIMO for mitigating radio-wave path loss and increasing radio-wave transmission distances in mmWave, supporting numerologies (for example, operating multiple subcarrier spacings) for efficiently utilizing mmWave resources and dynamic operation of slot formats, initial access technologies for supporting multi-beam transmission and broadbands, definition and operation of BWP (BandWidth Part), new channel coding methods such as a LDPC (Low Density Parity Check) code for large amount of data transmission and a polar code for highly reliable transmission of control information, L2 pre-processing, and network slicing for providing a dedicated network specialized to a specific service.

[0004] Currently, there are ongoing discussions regarding improvement and performance enhancement of initial 5G mobile communication technologies in view of services to be supported by 5G mobile communication technologies, and there has been physical layer standardization regarding technologies such as V2X (Vehicle-to-everything) for aiding driving determination by autonomous vehicles based on information regarding positions and states of vehicles transmitted by the vehicles and for enhancing user convenience, NR-U (New Radio Unlicensed) aimed at system operations conforming to various regulation-related requirements in unlicensed bands, NR UE Power Saving, Non-Terrestrial Network (NTN) which is UE-satellite direct communication for providing coverage in an area in which communication with terrestrial networks is unavailable, and positioning.

[0005] Moreover, there has been ongoing standardization in air interface architecture / protocol regarding technologies such as Industrial Internet of Things (IIoT) for supporting new services through interworking and convergence with other industries, IAB (Integrated Access and Backhaul) for providing a node for network service area expansion by supporting a wireless backhaul link and an access link in an integrated manner, mobility enhancement including conditional handover and DAPS (Dual Active Protocol Stack) handover, and two-step random access for simplifying random access procedures (2-step RACH for NR). There also has been ongoing standardization in system architecture / service regarding a 5G baseline architecture (for example, service based architecture or service based interface) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) for receiving services based on UE positions.

[0006] As 5G mobile communication systems are commercialized, connected devices that have been exponentially increasing will be connected to communication networks, and it is accordingly expected that enhanced functions and performances of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is scheduled in connection with eXtended Reality (XR) for efficiently supporting AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality) and the like, 5G performance improvement and complexity reduction by utilizing Artificial Intelligence (AI) and Machine Learning (ML), AI service support, metaverse service support, and drone communication.

[0007] Furthermore, such development of 5G mobile communication systems will serve as a basis for developing not only new waveforms for providing coverage in terahertz bands of 6G mobile communication technologies, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), array antennas and large-scale antennas, metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional space multiplexing technology using OAM (Orbital Angular Momentum), and RIS (Reconfigurable Intelligent Surface), but also full-duplex technology for increasing frequency efficiency of 6G mobile communication technologies and improving system networks, AI-based communication technology for implementing system optimization by utilizing satellites and AI (Artificial Intelligence) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for implementing services at levels of complexity exceeding the limit of UE operation capability by utilizing ultra-high-performance communication and computing resources.

[0008] The above information is presented as background information only to assist with an understanding of the disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the disclosure.

[0009] The present disclosure provides a configuration scheme for a grant-free contention PUSCH transmission.

[0010] The technical objects to be achieved by various embodiments of the disclosure are not limited to the technical objects mentioned above, and other technical objects not mentioned may be considered by those skilled in the art from various embodiments of the disclosure to be described below.

[0011] The present disclosure provides a configuration scheme for a grant-free contention PUSCH transmission. A user selects a non-orthogonal or orthogonal grant-free resource based on contention to perform the PUSCH transmission, and adjusts a resource used for a next transmission (e.g., a retransmission or a new transmission) according to detected DCI, to obtain a dynamic compromise between the number of supported users and transmission quality.

[0012] According to at least one embodiment of the present disclosure, there is provided a method performed by a user equipment UE in a communication system, including: receiving first information, wherein, the first information includes information related to a plurality of resource sets; using a first resource to perform a first grant-free transmission, the first resource belonging to a first resource set among the plurality of resource sets; in case that second information is received in response to the first grant-free transmission and the first grant-free transmission is unsuccessful, determining a second resource used for a retransmission based on the second information, and using the second resource to perform the retransmission, the second resource belonging to a second resource set among configured resource sets.

[0013] In an implementation, the method further includes: in case that the second information is not received, determining that the first grant-free transmission is unsuccessful, and using a third resource to perform the retransmission; wherein, the third resource belongs to a resource set that is different from the first resource set among the configured resource sets, and a first parameter of the resource set to which the third resource belongs is smaller than a first parameter of the first resource set; the first parameter indicates a ratio of the number of non-orthogonal UEs that resources in the resource set can support to the number of orthogonal UEs that the resources in the resource set can support.

[0014] In an implementation, the second information includes at least one of: information indicating whether the first grant-free transmission is successful, timing advance information, UE identity information, and CSI related information.

[0015] In an implementation, the second resource is determined from the configured resource sets, based on the CSI related information; or, a first parameter of the second resource set to which the second resource belongs is not smaller than the first parameter of the first resource set, wherein, the first parameter indicates the ratio of the number of non-orthogonal UEs that the resources in the resource set can support to the number of orthogonal UEs that the resources in the resource set can support.

[0016] In an implementation, whether the first grant-free transmission is successful is determined based on the information included in the second information that indicates whether the first grant-free transmission is successful; or, if the UE identity information included in the second information is inconsistent with the identity information of the UE, determining that the first grant-free transmission is unsuccessful.

[0017] In an implementation, the CSI related information includes level information of the CSI and / or a value of the CSI.

[0018] In an implementation, the second information includes resource information used for a new transmission and / or configuration parameter information corresponding to the new transmission; and the method further includes: in case that the first grant-free transmission is successful, performing a new transmission based on the second information.

[0019] In an implementation, the first resource set is determined from the plurality of resource sets by at least one of ways below: random selection; a resource set whose first parameter is the largest among the plurality of resource sets; determining the CSI level based on the CSI related information of the UE, and determining the first parameter corresponding to the determined CSI level based on a corresponding relationship between the CSI level and the first parameter; determining the first resource set based on a first parameter corresponding to a resource set to which resources of a previous grant-free transmission of the UE belongs; determining the first resource set according to redundancy corresponding to each resource set among the plurality of resource sets determined based on a buffer status of the UE; wherein, the first parameter indicates the ratio of the number of non-orthogonal UEs that the resources in the resource set can support to the number of orthogonal UEs that the resources in the resource set can support.

[0020] In an implementation, the configured resource sets refer to a plurality of resource sets determined based on the first information, or a plurality of resource sets determined based on most recently received first information.

[0021] In an implementation, the first grant-free transmission includes at least one of information below: information indicating whether the transmission is completed, information related to the buffer status of the UE, information indicating whether to apply for dedicated resources, information identifying the UE identity, and information indicating whether to apply for access.

[0022] In an implementation, the first information includes configuration information of the plurality of resource sets, and the configuration information includes: at least one of time domain resource information, frequency domain resource information, and multiple access resource information of each resource set among the plurality of resource sets.

[0023] In an implementation, a configuration parameter related to grant-free transmission corresponding to each resource set is included in the first information; or the configuration parameter related to grant-free transmission corresponding to each resource set is preset.

[0024] In an implementation, the method further includes: receiving a third information, wherein, the third information includes a configuration parameter related to grant-free transmission corresponding to each resource set.

[0025] In an implementation, the configuration parameter related to grant-free transmission includes at least one of the modulation and coding scheme MCS and a transmission power control parameter.

[0026] According to at least one embodiment of the present disclosure, there is provided a method performed by a base station in a communication system, including: transmitting first information, wherein, the first information includes information related to a plurality of resource sets; receiving a first grant-free transmission performed by using a first resource, the first resource belonging to a first resource set among the plurality of resource sets; transmitting second information in response to the first grant-free transmission, and in case that the first grant-free transmission is unsuccessful, receiving a retransmission performed by using a second resource, the second resource being determined based on the second information, and the second resource belonging to a second resource set among the configured resource sets.

[0027] In an implementation, the method further includes: receiving a retransmission performed by using a third resource; the third resource belonging to a resource set that is different from the first resource set among the configured resource sets, and a first parameter of the resource set to which the third resource belongs being smaller than a first parameter of the first resource set, wherein, the first parameter indicates a ratio of the number of non-orthogonal UEs that the resources in the resource set can support to the number of orthogonal UEs that the resources in the resource set can support.

[0028] In an implementation, the second information includes at least one of: information indicating whether the first grant-free transmission is successful, timing advance information, UE identity information, and CSI related information.

[0029] In an implementation, the second resource is determined from the configured resource sets, based on the CSI related information; or, a first parameter of the second resource set to which the second resource belongs is not smaller than the first parameter of the first resource set, wherein, the first parameter indicates the ratio of the number of non-orthogonal UEs that the resources in the resource set can support to the number of orthogonal UEs that the resources in the resource set can support.

[0030] In an implementation, the CSI related information includes level information of the CSI and / or a value of the CSI.

[0031] In an implementation, the second information includes resource information used for a new transmission and / or configuration parameter information corresponding to the new transmission; and the method further includes: in case that the grant-free transmission is successful, receiving the new transmission performed based on the second information.

[0032] In an implementation, the first resource set is determined from the plurality of resource sets by ways below: random selection; a resource set whose first parameter is the largest among the plurality of resource sets; determining the CSI level based on the CSI related information, and determining the first parameter corresponding to the determined CSI level based on a corresponding relationship between the CSI level and the first parameter; determining the first resource set based on a first parameter corresponding to a resource set to which resources of a previous grant-free transmission of the UE belongs; determining the first resource set according to redundancy corresponding to each resource set among the plurality of resource sets determined based on a buffer status of the UE; wherein, the first parameter indicates the ratio of the number of non-orthogonal UEs that the resources in the resource set can support to the number of orthogonal UEs that the resources in the resource set can support.

[0033] In an implementation, the configured resource sets include a plurality of resource sets configured by the first information or a plurality of resource sets configured by the most recently transmitted first information.

[0034] In an implementation, the first grant-free transmission includes at least one of information below: information indicating whether the transmission is completed, information related to the buffer status of the UE, information indicating whether to apply for dedicated resources, information identifying the UE identity, and information indicating whether to apply for access.

[0035] In an implementation, the first information includes configuration information of the plurality of resource sets, and

[0036] wherein, the configuration information includes: at least one of time domain resource information, frequency domain resource information, and multiple access resource information of each resource set among the plurality of resource sets.

[0037] In an implementation, a configuration parameter related to grant-free transmission corresponding to each resource set is included in the first information; or the configuration parameter related to grant-free transmission corresponding to each resource set is preset.

[0038] In an implementation, the method further includes: transmitting third information, wherein, the third information includes a configuration parameter related to grant-free transmission corresponding to each resource set.

[0039] In an implementation, the configuration parameter related to grant-free transmission includes at least one of modulation and coding scheme MCS and a transmission power control parameter.

[0040] According to at least one embodiment of the present disclosure, there is provided a user equipment UE, including: a transceiver, configured to transmit and / or receive data or signals; and a controller, configured to perform control such that the UE performs the method according to the embodiment of the present disclosure.

[0041] According to at least one embodiment of the present disclosure, there is provided a base station, including: a transceiver, configured to transmit and / or receive data or signals; and a controller, configured to perform control such that the base station performs the method according to the embodiment of the present disclosure.

[0042] The above-described various embodiments of the disclosure are merely some of the preferred embodiments of the disclosure, and various embodiments reflecting the technical features of the disclosure may be derived and understood by those skilled in the art based on the following detailed description of the disclosure.

[0043] The present disclosure provides a configuration scheme for a grant-free contention PUSCH transmission.

[0044] The effects that can be achieved through the disclosure are not limited to the effects mentioned in the various embodiments, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

[0045] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

[0046] FIG. 1 illustrates an example wireless network according to embodiments of the present disclosure;

[0047] FIG. 2 illustrates an example base station according to embodiments of the present disclosure;

[0048] FIG. 3 illustrates an example user equipment according to embodiments of the present disclosure;

[0049] FIG. 4 shows a schematic diagram of a method 400 for performing a grant-free transmission by a user according to embodiments of the present disclosure;

[0050] FIG. 5 shows a schematic diagram of a grant-free resource according to embodiments of the present disclosure;

[0051] FIG. 6 shows a flow chart of a resource set selecting method according to embodiments of the present disclosure;

[0052] FIG. 7 shows a flow chart of a method for determining a second resource related to a new transmission by a user according to embodiments of the present disclosure;

[0053] FIG. 8 shows a flow chart of a method for determining a second resource related to a retransmission by a user according to embodiments of the present disclosure;

[0054] FIG. 9 shows a flow chart of a method for determining a second resource related to a retransmission by a user who has not received the second information according to embodiments of the present disclosure;

[0055] FIG. 10 shows a flow chart of a method 1000 for determining a second resource related to a retransmission by a non-access user according to embodiments of the present disclosure;

[0056] FIG. 11 shows a simple block diagram of a hardware structure of a user equipment UE according to embodiments of the present disclosure; and

[0057] FIG. 12 shows a simple block diagram of a hardware structure of a base station according to embodiments of the present disclosure.

[0058] Before undertaking the DETAILED DESCRIPTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term "couple" and its derivatives refer to any direct or indirect communication between two or more elements, whether those elements are in physical contact with one another. The terms "transmit," "receive," and "communicate," as well as derivatives thereof, encompass both direct and indirect communication. The terms "include" and "comprise," as well as derivatives thereof, mean inclusion without limitation. The term "or" is inclusive, meaning and / or. The phrase "associated with," as well as derivatives thereof, means to include, be included within, interconnect with, contain, be included within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The term "controller" means any device, system or part thereof that controls at least one operation. Such a controller may be implemented in hardware or a combination of hardware and software and / or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. The phrase "at least one of," when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be needed. For example, "at least one of: A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C. Likewise, the term "set" means one or more. Accordingly, a set of items may be a single item or a collection of two or more items.

[0059] Moreover, various functions described below may be implemented or supported by one or more computer programs, each of which is formed from computer readable program code and embodied in a computer readable medium. The terms "application" and "program" refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion thereof adapted for implementation in a suitable computer readable program code. The phrase "computer readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer readable medium" includes any type of medium capable of being accessed by a computer, such as read only memory (ROM), random access memory (RAM), a hard disk drive, a compact disc (CD), a digital video disc (DVD), or any other type of memory. A "non-transitory" computer readable medium excludes wired, wireless, optical, or other communication links that transport transitory electrical or other signals. A non-transitory computer readable medium includes media where data may be permanently stored and media where data may be stored and later overwritten, such as a rewritable optical disc or an erasable memory device.

[0060] Definitions for other certain words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many if not most instances, such definitions apply to prior as well as future uses of such defined words and phrases.

[0061] The figures included herein, and the various embodiments used to describe the principles of the present disclosure are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Further, those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged wireless communication system.

[0062] Considering the development of wireless communication from generation to generation, the technologies have been developed mainly for services targeting humans, such as voice calls, multimedia services, and data services. Following the commercialization of 5th-generation (5G) communication systems, it is expected that the number of connected devices will exponentially grow. Increasingly, these will be connected to communication networks. Examples of connected things may include vehicles, robots, drones, home appliances, displays, smart sensors connected to various infrastructures, construction machines, and factory equipment. Mobile devices are expected to evolve in various form-factors, such as augmented reality glasses, virtual reality headsets, and hologram devices. In order to provide various services by connecting hundreds of billions of devices and things in the 6th-generation (6G) era, there have been ongoing efforts to develop improved 6G communication systems. For these reasons, 6G communication systems are referred to as beyond-5G systems.

[0063] 6G communication systems, which are expected to be commercialized around 2030, will have a peak data rate of tera (1,000 giga)-level bps and a radio latency less than 100μsec, and thus will be 50 times as fast as 5G communication systems and have the 1 / 10 radio latency thereof.

[0064] In order to accomplish such a high data rate and an ultra-low latency, it has been considered to implement 6G communication systems in a terahertz band (for example, 95GHz to 3THz bands). It is expected that, due to severer path loss and atmospheric absorption in the terahertz bands than those in mmWave bands introduced in 5G, technologies capable of securing the signal transmission distance (that is, coverage) will become more crucial. It is necessary to develop, as major technologies for securing the coverage, radio frequency (RF) elements, antennas, novel waveforms having a better coverage than orthogonal frequency division multiplexing (OFDM), beamforming and massive multiple input multiple output (MIMO), full dimensional MIMO (FD-MIMO), array antennas, and multiantenna transmission technologies such as large-scale antennas. In addition, there has been ongoing discussion on new technologies for improving the coverage of terahertz-band signals, such as metamaterial-based lenses and antennas, orbital angular momentum (OAM), and reconfigurable intelligent surface (RIS).

[0065] Moreover, in order to improve the spectral efficiency and the overall network performances, the following technologies have been developed for 6G communication systems: a full-duplex technology for enabling an uplink transmission and a downlink transmission to simultaneously use the same frequency resource at the same time; a network technology for utilizing satellites, high-altitude platform stations (HAPS), and the like in an integrated mode; an improved network structure for supporting mobile base stations and the like and enabling network operation optimization and automation and the like; a dynamic spectrum sharing technology via collision avoidance based on a prediction of spectrum usage; an use of artificial intelligence (AI) in wireless communication for improvement of overall network operation by utilizing AI from a designing phase for developing 6G and internalizing end-to-end AI support functions; and a next-generation distributed computing technology for overcoming the limit of user equipment (UE) computing ability through reachable super-high-performance communication and computing resources (e.g., mobile edge computing (MEC), clouds, and the like) over the network. In addition, through designing new protocols to be used in 6G communication systems, developing mechanisms for implementing a hardware-based security environment and safe use of data, and developing technologies for maintaining privacy, attempts to strengthen the connectivity between devices, optimize the network, promote softwarization of network entities, and increase the openness of wireless communications are continuing.

[0066] It is expected that research and development of 6G communication systems in hyper-connectivity, including person to machine (P2M) as well as machine to machine (M2M), will allow the next hyper-connected experience. Particularly, it is expected that services such as truly immersive extended reality (XR), high-fidelity mobile hologram, and digital replica could be provided through 6G communication systems. In addition, services such as remote surgery for security and reliability enhancement, industrial automation, and emergency response will be provided through the 6G communication system such that the technologies could be applied in various fields such as industry, medical care, automobiles, and home appliances.

[0067] FIGS. 1-12 below describe various embodiments of the present disclosure implemented in wireless communications systems. The descriptions of FIGS. 1-12 are not meant to imply physical or architectural limitations to the mode in which different embodiments may be implemented. Different embodiments of the present disclosure may be implemented in any suitably-arranged communications system.

[0068] FIG. 1 illustrates an example wireless network according to embodiments of the present disclosure. The embodiment of the wireless network shown in FIG. 1 is for illustration only. Other embodiments of the wireless network 100 could be used without departing from the scope of the present disclosure.

[0069] As shown in FIG. 1, the wireless network includes a base station (next generation nodeB, gNB or gNodeB) 101, a gNB 102, and a gNB 103. The gNB 101 communicates with the gNB 102 and the gNB 103. The gNB 101 also communicates with at least one network 130, such as the Internet, a proprietary Internet Protocol (IP) network, or other data network.

[0070] The gNB 102 provides wireless broadband access to the network 130 for a first plurality of user equipments (UEs) within a coverage area 120 of the gNB 102. The first plurality of UEs includes a UE 111, which may be located in a small business; a UE 112, which may be located in an enterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); a UE 114, which may be located in a first residence (R1); a UE 115, which may be located in a second residence (R2); and a UE 116, which may be a mobile device (M), such as a cell phone, a wireless laptop, a wireless personal digital assistant (PDA), or the like. The gNB 103 provides wireless broadband access to the network 130 for a second plurality of UEs within a coverage area 125 of the gNB 103. The second plurality of UEs includes the UE 115 and the UE 116, as well as subscriber stations (SS, for example, UEs) 117, 118 and 119. In some embodiments, one or more of the gNBs 101-103 may communicate with each other and with the UEs 111-116 using existing wireless communication techniques, and one or more of the UE 111-119 may communicate directly with each other (e.g., UEs 117-119) using other existing or proposed wireless communication techniques.

[0071] Depending on the network type, the term "base station" or "BS" may refer to any component (or collection of components) configured to provide wireless access to a network, such as transmit point (TP), transmit-receive point (TRP), an enhanced (or "evolved") base station (eNodeB or eNB), a 5G base station (gNB), a macrocell, a femtocell, a wireless fidelity (WiFi) access point (AP), or other wirelessly enabled devices. Base stations may provide wireless access in accordance with one or more wireless communication protocols, e.g., 3GPP 5G New Radio (NR), Long Term Evolution (LTE), LTE Advanced (LTE-A), high speed packet access (HSPA), Wi-Fi 802.11a / b / g / n / ac, etc. For the sake of convenience, the various names for a base station-type apparatus and functionality are used interchangeably in this patent document to refer to network infrastructure components that provide wireless access to remote terminals. Also, depending on the network type, the term "user equipment" (UE) may refer to any component such as a mobile station (MS), subscriber station (SS), remote terminal, wireless terminal, receive point, or user equipment. For the sake of convenience, the various names for a user equipment-type device and functionality are used interchangeably in this patent document to refer to remote wireless equipment that wirelessly accesses a BS, whether the UE is a mobile device (e.g., a mobile telephone or smartphone) or is normally considered a stationary device (e.g., a desktop computer or vending machine).

[0072] Dotted lines show the approximate extents of the coverage areas 120 and 125, which are shown as approximately circular for the purposes of illustration and explanation only. It should be clearly understood that the coverage areas associated with gNBs, such as the coverage areas 120 and 125, may have other shapes, including irregular shapes, depending upon the configuration of the gNBs and variations in the radio environment associated with natural and man-made obstructions.

[0073] As described in more detail below, one or more of the UEs 111-119 include circuitry, programing, or a combination thereof. In certain embodiments, and one or more of the gNBs 101-103 includes circuitry, programing, or a combination thereof.

[0074] Although FIG. 1 illustrates one example of a wireless network, various changes may be made to FIG. 1. For example, the wireless network could include any number of gNBs and any number of UEs in any suitable arrangement. Also, the gNB 101 could communicate directly with any number of UEs and provide those UEs with wireless broadband access to the network 130. Similarly, each gNB 102-103 could communicate directly with the network 130 and provide UEs with direct wireless broadband access to the network 130. Further, the gNBs 101, 102, and / or 103 could provide access to other or additional external networks, such as external telephone networks or other types of data networks.

[0075] FIG. 2 illustrates an example base station according to embodiments of the present disclosure. The embodiment of the gNB 102 illustrated in FIG. 2 is for illustration only, and the gNBs 101 and 103 of FIG. 1 could have the same or similar configuration. However, gNBs come in a wide variety of configurations, and FIG. 2 does not limit the scope of the present disclosure to any particular implementation of a gNB.

[0076] As shown in FIG. 2, the gNB 102 includes multiple antennas 200a-200n, multiple radio frequency (RF) transceivers 201a-201n, transmit (TX) processing circuitry 203, and receive (RX) processing circuitry 204. The gNB 102 also includes a controller / processor 205, a memory 206, and a backhaul or network interface 207.

[0077] The RF transceivers 201a-201n receive, from the antennas 200a-200n, incoming RF signals, such as signals transmitted by UEs in the network 100. The RF transceivers 201a-201n down-convert the incoming RF signals to generate intermediate frequency (IF) or baseband signals. The IF or baseband signals are sent to the RX processing circuitry 204, which generates processed baseband signals by filtering, decoding, and / or digitizing the baseband or IF signals. The RX processing circuitry 204 transmits the processed baseband signals to the controller / processor 205 for further processing.

[0078] The TX processing circuitry 203 receives analog or digital data (such as voice data, web data, electronic mail, or interactive video game data) from the controller / processor 205. The TX processing circuitry 203 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate processed baseband or IF signals. The RF transceivers 201a-201n receive the outgoing processed baseband or IF signals from the TX processing circuitry 203 and up-converts the baseband or IF signals to RF signals that are transmitted via the antennas 201a-201n.

[0079] The controller / processor 205 may include one or more processors or other processing devices that control the overall operation of the gNB 102. For example, the controller / processor 205 could control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceivers 201a-201n, the RX processing circuitry 204, and the TX processing circuitry 203 in accordance with well-known principles. The controller / processor 205 could support additional functions as well, such as more advanced wireless communication functions.

[0080] For instance, the controller / processor 205 could support beam forming or directional routing operations in which outgoing signals from multiple antennas 200a-200n are weighted differently to effectively steer the outgoing signals in a desired direction. Any of a wide variety of other functions could be supported in the gNB 102 by the controller / processor 205.

[0081] The controller / processor 205 is also capable of executing programs and other processes resident in the memory 206, such as an operating system (OS). The controller / processor 205 can move data into or out of the memory 206 as required by an executing process.

[0082] The controller / processor 205 is also coupled to the backhaul or network interface 207. The backhaul or network interface 207 allows the gNB 102 to communicate with other devices or systems over a backhaul connection or over a network. The interface 207 could support communications over any suitable wired or wireless connection(s). For example, when the gNB 102 is implemented as part of a cellular communication system (e.g., one supporting 5G, LTE, or LTE-A), the interface 207 could allow the gNB 102 to communicate with other gNBs over a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, the interface 207 could allow the gNB 102 to communicate over a wired or wireless local area network or over a wired or wireless connection to a larger network (e.g., the Internet). The interface 207 includes any suitable structure supporting communications over a wired or wireless connection, such as an Ethernet or RF transceiver.

[0083] The memory 206 is coupled to the controller / processor 205. Part of the memory 206 could include a random access memory (RAM), and another part of the memory 206 could include a Flash memory or other read only memory (ROM).

[0084] Although FIG. 2 illustrates one example of gNB 102, various changes may be made to FIG. 2. For example, the gNB 102 could include any number of each component shown in FIG. 2. As a particular example, an access point could include a number of interfaces 207, and the controller / processor 205 could support routing functions to route data between different network addresses. As another particular example, while shown as including a single instance of TX processing circuitry 203 and a single instance of RX processing circuitry 204, the gNB 102 could include multiple instances of each (e.g., one per RF transceiver). Also, various components in FIG. 2 could be combined, further subdivided, or omitted and additional components could be added according to particular needs.

[0085] FIG. 3 illustrates an example user equipment according to embodiments of the present disclosure. The embodiment of the UE 116 illustrated in FIG. 3 is for illustration only, and the UEs 111-115 and 117-119 of FIG. 1 could have the same or similar configuration. However, UEs come in a wide variety of configurations, and FIG. 3 does not limit the scope of the present disclosure to any particular implementation of a UE.

[0086] As shown in FIG. 3, the UE 116 includes an antenna 301, a radio frequency (RF) transceiver 302, TX processing circuitry 303, a microphone 304, and receive (RX) processing circuitry 305. The UE 116 also includes a speaker 306, a controller or processor 307, an input / output (I / O) interface (IF) 308, an input device 309, a touchscreen display 310, and a memory 311. The memory 311 includes an OS 312 and one or more applications 313.

[0087] The RF transceiver 302 receives, from the antenna 301, an incoming RF signal transmitted by a gNB of the network 100. The RF transceiver 302 down-converts the incoming RF signal to generate an IF or baseband signal. The IF or baseband signal is sent to the RX processing circuitry 305, which generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuitry 305 transmits the processed baseband signal to the speaker 306 (e.g., for voice data) or to the processor 307 for further processing (e.g., for web browsing data).

[0088] The TX processing circuitry 303 receives analog or digital voice data from the microphone 304 or other outgoing baseband data (e.g., web data, e-mail, or interactive video game data) from the processor 307. The TX processing circuitry 303 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 302 receives the outgoing processed baseband or IF signal from the TX processing circuitry 303 and up-converts the baseband or IF signal to an RF signal that is transmitted via the antenna 301.

[0089] The processor 307 may include one or more processors or other processing devices and execute the OS 312 stored in the memory 311 in order to control the overall operation of the UE 116. For example, the processor 307 could control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceiver 302, the RX processing circuitry 305, and the TX processing circuitry 303 in accordance with well-known principles. In some embodiments, the processor 307 includes at least one microprocessor or microcontroller.

[0090] The processor 307 is also capable of executing other processes and programs resident in the memory 311, such as processes for channel state information (CSI) reporting on uplink channel. The processor 307 can move data into or out of the memory 311 as required by an executing process. In some embodiments, the processor 307 is configured to execute the applications 313 based on the OS 312 or in response to signals received from gNBs or an operator. The processor 307 is also coupled to the I / O interface 308, which provides the UE 116 with the ability to connect to other devices, such as laptop computers and handheld computers. The I / O interface 308 is the communication path between these accessories and the processor 307.

[0091] The processor 307 is also coupled to the touchscreen display 310. The user of the UE 116 can use the touchscreen display 310 to enter data into the UE 116. The touchscreen display 310 may be a liquid crystal display, light emitting diode display, or other display capable of rendering text and / or at least limited graphics, such as from web sites.

[0092] The memory 311 is coupled to the processor 307. Part of the memory 311 could include RAM, and another part of the memory 311 could include a Flash memory or other ROM.

[0093] Although FIG. 3 illustrates one example of UE 116, various changes may be made to FIG. 3. For example, various components in FIG. 3 could be combined, further subdivided, or omitted and additional components could be added according to particular needs. As a particular example, the processor 307 could be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). Also, while FIG. 3 illustrates the UE 116 configured as a mobile telephone or smartphone, UEs could be configured to operate as other types of mobile or stationary devices.

[0094] The embodiments of the present disclosure will be described in more detail below in conjunction with the accompanying drawings. It should be understood that throughout the description of the present disclosure, for convenience of description and easy to understand, sometimes descriptions such as "user", "user equipment", "UE", etc. are used; and it may be understood that they may be interchanged.

[0095] The next generation of mobile communication is facing broader and more diverse application scenarios, and therefore, the number of users who need to transmit uplink data is also growing explosively. The uplink transmission mechanism in the 5G New Radio (NR) standard is grant-based. A user needs to perform signaling interaction with the base station so as to obtain uplink resource grant. With respect to a user who transmits a small amount of data (from a few bits to a few hundred bits), signaling overhead becomes non-ignorable as compared with costs of data transmission. In order to reduce signaling overhead of users, a grant-free transmission mechanism allows a user to transmit uplink data without obtaining grant from the base station. Moreover, the grant-free transmission mechanism may also reduce access latency caused by signaling interaction. Grant-free transmission is divided into contention-based grant-free transmission and contention free grant-free transmission. In a contention free grant-free transmission mechanism, a user performs uplink transmission in the user's dedicated grant-free transmission resources. Since user does not always have data to transmit, the contention free grant-free transmission mode has a lower resource utilization rate.

[0096] In contention-based grant-free transmission, the base station assigns a same grant-free transmission resource set to a plurality of users. An active user having data to transmit selects a multiple access resource from the resource set to perform uplink data transmission. The multiple access resource may be a resource distinguished according to at least one of: interleaving mode, spreading sequence, scrambling code sequence, resource mapping mode, power assigning mode, etc. Since all users randomly select resources for use from a common resource set, collisions may occur, that is, a plurality of active users select a same resource to transmit data, which affects decoding performance of the base station. Therefore, it is necessary to enhance contention-based grant-free transmission, so as to improve performance of data transmission.

[0097] By increasing the number of multiple access resources in the resources, a probability of collisions may be effectively reduced. However, since communication resources (e.g., resources in at least one of time domain, frequency domain, code domain, and space domain) are limited, and a non-orthogonal resource multiplexing mode may increase the number of available multiple access resources, uplink transmission of more users can be supported. Wherein, a ratio of the number of users that can be supported in a non-orthogonal mode to the number of users that can be supported in an orthogonal mode by resources occupied by a resource set (e.g., resources in at least one of time domain, frequency domain, space domain, or code domain; for ease of description, description is given by taking "time-frequency-space domain resources" or "time-frequency-code domain resources" as examples) may be taken as a parameter measuring the resource set, which is referred to as a first parameter; for convenience of description and ease of understanding, in description hereinafter, the first parameter is referred to as a non-orthogonal multiplex degree of the resource set. For example, assuming a plurality of users use the same resources (e.g., time-frequency-space resource) for transmission, and different users are distinguished by using different spreading sequences, the spreading codes have a length of L and a quantity of N (N>L), then the number of users that can be orthogonally supported by the time-frequency-code domain resources is L, and the number of users that can be non-orthogonally supported is N, then the non-orthogonal multiplex degree of the time-frequency-code domain resource is N / L. For example, a non-orthogonal multiplex degree of an orthogonal resource set is 1. The number of users that can be supported by the resource set increases with increase of the non-orthogonal multiplex degree; but higher non-orthogonal multiplex degree also brings higher inter-user interference, which affects a success rate of decoding received data by the base station. Therefore, how to determine a grant-free resource set of a corresponding non-orthogonal multiplex degree for transmission is one of the urgent problems that need to be solved in grant-free transmission.

[0098] The present disclosure proposes an uplink resource configuration scheme based on grant-free transmission; a user determines a grant-free transmission resource for use according to multiple information, and adjusts a resource used for a next transmission (e.g., a new transmission or a retransmission) according to information fed back by the base station, which allows for a compromise between the number of users in multi-user uplink transmission and uplink data rate for a single-user, maximizes a resource utilization rate, reduces the number of retransmissions for grant-free transmission by users, and extends service life for users.

[0099] In an implementation, retransmission may refer to transmitting same data bits (e.g., an uplink shared channel transport block UL-SCH transmission block) by a user again after failure of the grant-free transmission, the data bits are transmitted using the same Redundancy Version (RV) as the previous grant-free transmission. In addition, the retransmission as mentioned in the description of the present disclosure may also be retransmission related to HARQ, where the user retransmits data of a different RV version. In addition, the principles according to the present disclosure may also be applied to other retransmissions.

[0100] In an implementation, new transmission or a new transmission as described throughout the present disclosure may refer to an initial transmission of data, which for example, is relative to retransmission of the data.

[0101] FIG. 4 shows a schematic diagram of a method 400 for performing a grant-free transmission by a user according to embodiments of the present disclosure.

[0102] As shown in FIG. 4, the method 400 includes at least some of steps below:

[0103] Step 401: receiving first information, and determining a plurality of (e.g. at least two) resource sets according to the first information;

[0104] Step 402: selecting a resource set (a first resource set) from the plurality of resource sets, selecting a grant-free first resource from the selected resource set (first resource set), and using the selected first resource to perform uplink transmission;

[0105] Step 403: receiving second information, and determining whether the uplink transmission is successful;

[0106] Step 404: determining a second resource associated with a next transmission (e.g., a new transmission or a retransmission); and

[0107] Step 405: using the second resource to perform the next transmission.

[0108] In an implementation, the new transmission may be either grant-free transmission or grant-based transmission.

[0109] In some examples, when a user has completed initial access and is in a connected state, the first information may be obtained through at least one of: system messages (e.g., Master Information Block (MIB), System Information Block (SIB), etc.), high-level signaling, Downlink Control Information (DCI), wherein, a Physical Downlink Control Channel (PDCCH) carrying DCI may be obtained by the user searching in Common Search Space (CSS) or in User-specific Search Space (USS); or, when the user has not completed initial access and has not set up an RRC connection with the base station, a first message may be obtained through system messages (e.g., MIB, SIB, etc.). In a specific implementation of these examples, an access user and a non-access user obtain same first information, for example, the access user and the non-access user receive a same system message and obtain a same resource set therefrom. Assigning the same resource set for the access user and the non-access user may reduce occupancy of system message resources. In another specific implementation of these examples, the access user and the non-access user obtain different first information. One possible implementation is that: the access user obtains, through high-level signaling or DCI, a resource set exclusively used by the access user, and the non-access user obtains, through the system messages, a resource set exclusively used by the non-access user. When a user state changes, for example, from access to non-access, or from non-access to access, the user receives the first information again, and obtains a new resource set. Since the base station is unaware of the data transmission situation of the user, blind detection is required. By assigning different resource sets for the access user and the non-access user, the base station may distinguish different types of users according to the first resource in the resource set, thereby reducing computational complexity of reception and decoding by the base station.

[0110] In other examples, the first information includes configuration information of the resource set, which is used for obtaining information such as time-frequency resources and / or multiple access resources used by a user used for uplink grant-free transmission in grant-free transmission. In a specific implementation of these examples, the configuration information of the resource set includes at least one of: time domain resource information (e.g., location and size of time domain resources), frequency domain resource information (e.g., location and size of frequency domain resources), multiple access resource information (e.g., type of multiple access resources, the number of multiple access resources, and other information of multiple access resources), etc. In an OFDM system, the location and the size of the time domain resources may include: the number of time slots, the number of starting symbols, the number of symbols in duration, etc.; the location of and the frequency domain resources may include: Physical Resource Block (PRB) index, Resource Block Group (RBG), BandWidth Part (BWP), etc. The multiple access resource may be a resource distinguished according to at least one of: interleaving mode, spreading sequence, scrambling code sequence, resource mapping mode, power assigning mode, etc. The number of multiple access resources refers to the number of first resources available for users to select from in the resource set. The other information of the multiple access resource may be information necessary for generating the spreading sequence and / or the scrambling code sequence. In other examples, at least one of the time domain resource information, the frequency domain resource information, and the multiple access resource information of the resource set is preset. For example, in another specific implementation of these examples, location and size information of time-frequency resources for performing grant-free transmission by the user is preset information. The configuration information of the resource set may include the information below: type of multiple access resource, the number of multiple access resources, other information of multiple access resource, etc. The user obtains multiple access resource information of grant-free transmission according to the first information. Wherein, fixing the time-frequency resources of grant-free uplink transmission may reduce resource occupancy of the base station for notifying the first information.

[0111] In other examples, the first information further includes configurations and parameters required for grant-free uplink transmission performed by the user, including but not limited to Modulation and Coding Scheme (MCS), transmission power control, and other information. In one embodiment of these examples, each first resource set included in the first information may be configured with different uplink transmission configuration parameters. For example, when non-orthogonal multiplex degrees of all resource sets are all 1, that is, the base station configures orthogonal resources for all resource sets, since the base station may be unaware of uplink channel state quality of the user, the base station may configure different transmission parameters for these resource sets, to meet redundancy requirements for correct transmission by users in different channel states.

[0112] In other examples, the first information may be updated. For example, the first information is transmitted periodically; and the user receives the latest first information from the base station before each grant-free transmission. The first information is dynamically adjusted by the base station according to the access situation at a previous moment and / or the number of idle resources at a current moment. For example, when the base station detects that the number of multiple access resources used in the resource set exceeds a maximum value that the base station capable of solving for all and / or a signal-to-noise ratio of the received signal exceeds a certain threshold, the base station may select to perform at least one of adjustment strategies below according to current resource occupancy situation: increasing the number of resource sets, increasing the number of time-frequency resources of a single or each resource set, increasing a non-orthogonal multiplex degree of the resource set, etc. The adjustment strategy may increase the number of first resources available for the users, and reduce first resource collision probability that increases due to the increasing number of users who need to upload data, so as to increase the number of users for supporting multi-user uplink transmission. When the base station detects that the number of multiple access resources used in the resource set is low and / or the signal-to-noise ratio of the received signal exceeds a certain threshold, the base station may select to perform at least one of adjustment strategies below: reducing the number of resource sets, reducing the number of time-frequency resources of a single or each resource set, and reducing the non-orthogonal multiplex degree of the resource set. The adjustment strategy may increase the signal-to-noise ratio of the signals at the base station transmitted by the user, thereby improving data rate of a single-user.

[0113] In other examples, the plurality of resource sets included in the first information have different non-orthogonal multiplex degrees. Wherein, the non-orthogonal multiplex degrees may be calculated through information given by the first information. For example, if the base station configures four spread-spectrum-based resource sets, the four resource sets have the same number of time-frequency-space resources, lengths of the spreading sequences are all L, and the numbers of first resources pointed by the spreading sequence are respectively a*L, b*L, c*L, d*L, then the non-orthogonal multiplex degrees of the four resource sets are respectively a, b, c, d, and a relationship among the non-orthogonal multiplex degrees is a>b>c>d, as shown in (a) of FIG. 5. Wherein, resource sets with a higher non-orthogonal multiplex degree are capable of supporting more users to perform multi-user uplink transmission, while resource sets with a lower non-orthogonal multiplex degree are capable of providing a higher single-user uplink data rate. The base station may implement a compromise between the two by dynamically adjusting the non-orthogonal multiplex degrees of the resource sets.

[0114] In other examples, the plurality of resource sets included in the first information have a same non-orthogonal multiplex degree. For example, the non-orthogonal multiplex degree of the plurality of resource sets is 1. As a special case, when the non-orthogonal multiplex degree of the first resource set is 1, that is, all the first resources included in the first resource set are orthogonal to each other, for example, spreading sequences of any two first resources in the first resource set are orthogonal, etc. When the base station detects that the number of users performing grant-free uplink transmission is small, the base station may configure orthogonal resource sets to improve the single-user uplink data rate.

[0115] In other examples, time-frequency resource sizes of the plurality of resource sets indicated by the first information may be different, as shown in (b) of FIG. 5. In such case, a user may select a suitable resource set according to its own buffer status, thereby improving a resource utilization rate. Meanwhile, allowing the base station to configure different sizes of time-frequency resources also provides greater flexibility.

[0116] In other examples, the plurality of resource sets indicated by the first information may be set to different multiple access modes. For example, multiple access mode related to first resources in a resource set is spreading sequence, while multiple access mode related to first resources in another resource set is power domain multiple access. Users may select to use a different resource set in retransmission from that in initial transmission, so as to use different multiple access technologies to improve the single-user data rate.

[0117] In other examples, the resource sets have a same non-orthogonal multiplex degree and a same time-frequency resource size; and the method for determining the grant-free transmission resource set by the user may be randomly selecting one resource set from the at least two resource sets. For example, if the base station has sufficient resources and thus all resource sets are configured with orthogonal first resources, then all resource sets have a same non-orthogonal multiplex degree.

[0118] In other examples, the resource sets have a same non-orthogonal multiplex degree and different time-frequency resource sizes; and the method for determining the transmission resource set by the user may be based on the user buffer status. For example, in different application scenarios, the size of data bits that users need to transmission varies. By selecting a resource set of an appropriate size according to the buffer status, waste of time-frequency resources may be effectively avoided.

[0119] In other examples, the resource sets have different non-orthogonal multiplex degrees; and the non-orthogonal multiplex degrees may be given by the first information or be calculated through information given by the first information. The method for determining the grant-free transmission resource set by the user may be selecting at least one resource set according to at least one of following information (third information related to the user): Channel State Information (CSI), historical access information, and buffer status of the user.

[0120] FIG. 6 shows a flow chart of a resource set selecting method 600 according to embodiments of the present disclosure. As shown in FIG. 6, the method 600 includes:

[0121] Step 601: acquiring / calculating, by the UE, the non-orthogonal multiplex degree of the resource set according to the first information;

[0122] Step 602: determining, by the UE, whether there is third information; the third information including, for example, at least one of Channel State Information (CSI), historical access information, and buffer status of the UE. For example, the historical access information represents information related to one or more previous grant-free accesses of the UE, for example, information related to the resource set used for historical grant-free transmission (e.g., the non-orthogonal multiplex degree of the resource set used);

[0123] If a determination result of step 602 is YES, the method proceeds to step 603.

[0124] In step 603, the UE determines the first resource set with the corresponding non-orthogonal multiplex degree according to the third information.

[0125] If the determination result in step 602 is NO, the method proceeds to step 604.

[0126] In step 604, the UE randomly selects a resource set or selects a resource set with the highest non-orthogonal multiplex degree.

[0127] In a specific implementation of these examples, a method for selecting the first resource set by the user is: firstly, determining a channel state information level according to the channel state information of the user; then, retrieving non-orthogonal multiplex degree information of the resource sets included in the first information, or calculating non-orthogonal multiplex degree information of the resource sets according to other information in the first information; and then, selecting an appropriate resource set according to a corresponding relationship between the channel state level and the non-orthogonal multiplex degree.

[0128] For example, assuming that the channel state level is divided into four levels from high to low: 1, 2, 3, 4, and the channel state levels 1, 2, 3, 4 respectively correspond to orthogonal multiplex degrees a, b, c, d, if the user determines the channel state level as 2 and determines four resource sets with four non-orthogonal multiplex degrees respectively as a, b, c, d, where, a>b>c>d according to the first information, then the first resource set selected by the user is the resource set with the non-orthogonal multiplex degree of b.

[0129] Uplink channel quality of a user is taken as a most important factor affecting the uplink transmission data rate; the above-described resource set selecting method, by assigning a resource set with a higher non-orthogonal multiplex degree to a user with better channel quality, helps fully balance differences in data rates of user grant-free access caused by channel quality. Wherein, the method for acquiring channel state information by the user may be that it is obtained by calculating a downlink reference signal within channel reciprocity measurement coherent time or obtained by feedback from the base station.

[0130] In case that the user has no channel state information, a resource set with a high non-orthogonal multiplex degree may be preferentially selected to reduce probability of collisions, or a resource set may be randomly selected.

[0131] In another specific implementation of these examples, the method for selecting the first resource set by the user is: firstly, determining the non-orthogonal multiplex degree of the resource set used in the previous grant-free transmission; then, retrieving the non-orthogonal multiplex degree information of the resource sets included in the first information, or calculating the non-orthogonal multiplex degree information of the resource set according to other information in the first information; and then, selecting a resource set that is closest to the historically used non-orthogonal multiplex degree (e.g., the difference from the historically used non-orthogonal multiplex degree is within a certain threshold, or is the smallest).

[0132] For example, if the resource set used by the user to perform the last grant-free transmission is a resource set with a non-orthogonal multiplex degree of b and acknowledgment of successful transmission is received, then a resource set with a non-orthogonal multiplex degree equal to or close to b is preferentially selected for use this time. If there is no historical access information, a resource set with a high non-orthogonal multiplex degree may be preferentially selected to reduce probability of collisions, or a resource set may be randomly selected. The historical access information may to some extent reflect the uplink channel state of the user and the non-orthogonal multiplex degree that can be withstood. Selecting the first resource set according to the historical access information may effectively reduce the number of attempts for grant-free transmission by the user, wherein, the number of attempts is the number of transmissions performed by the user from starting a grant-free uplink transmission to receiving acknowledgment information of successful reception by the base station.

[0133] In another specific implementation of these examples, the method for selecting the first resource set by the user includes: calculating redundancy that each resource set can provide according to the first information and the buffer status; retrieving the non-orthogonal multiplex degree information of the resource set included in the first information, or calculating the non-orthogonal multiplex degree information of the resource set according to other information in the first information; and selecting an appropriate resource set according to the redundancy situation that the resource set can provide. Such a method may alleviate interference caused by resources with high non-orthogonal multiplex degree used by users through redundancy, and meanwhile, the saved resources may be used to support uplink transmission of more users.

[0134] In other examples, the mode of the user selecting a first resource from the selected first resource set may be: randomly selecting a first resource from a plurality of resources of the selected resource set. Wherein, each first resource uniquely determines the multiple access resource available for uplink transmission. The multiple access resource may be a resource distinguished according to at least one of: interleaving mode, spreading sequence, scrambling code sequence, resource mapping mode, power assigning mode, etc. Under a randomly selected strategy, probabilities of the user selecting each first resource in the resource set are equal, which may ensure lowest probability of first resource collision, and avoid unsuccessful uplink transmission caused by first resource collision.

[0135] In other examples, the configurations and the parameters required for grant-free uplink transmission performed by the user, including but not limited to MCS, transmission power control, and other information, are given by the first information. In such case, the base station may configure appropriate parameters for grant-free uplink transmission according to configuration situation of the first resource set, to improve a success rate of grant-free uplink transmission. For example, in case that resources for base station are relatively rich, if the base station configures a larger number of time-frequency resources for the first resource set, then the base station may configure a smaller MCS for the users to further improve the success rate of grant-free transmission, or configure a larger MCS to improve throughput.

[0136] In other examples, the configurations and the parameters required for grant-free uplink transmission performed by the user, including but not limited to MCS, transmission power control, and other information, are preset information. In such case, the base station does not need to consume additional resources to notify the user of the configurations and the parameters adopted, and the user does not need to consume resources to receive the configuration information.

[0137] In other examples, if the user has already been accessed, then the configurations and the parameters required for grant-free uplink transmission, including but not limited to MCS, transmission power control, and other information, are acquired through high-level signaling or DCI. If the user has not been accessed, then pre-configured parameters for grant-free uplink transmission will be used.

[0138] In other examples, if the user has already been accessed and assigned with C-RNTI, then C-RNTI is used to scramble the transmitted data; if the user has not been accessed and assigned with no C-RNTI, then the unique RNTI associated with the selected first resource is used to scramble the transmission data; and the base station may calculate the RNTI according to the first resource in the resource set.

[0139] In other examples, the data transmitted by the user may further include at least one of following items of information: indication of whether transmission is complete, buffer status, and indication of whether to apply for dedicated resources. With respect to a user not in connected state, the data transmitted thereby further includes a data bit identifying user identity information, for the base station to determine a source of the received data. In one embodiment of these examples, the data transmitted by the user not in connected state may include information indicating whether to apply for access, for example, RRC connection set-up information or RRC reestablishment information, etc.

[0140] In an implementation, the user receives the second information through DCI. In one embodiment of these examples, when the user has completed initial access and is in a connected state, the user receives the second information by obtaining CORSET and the user-specific search space USS through high-level configuration, and retrieving C-RNTI scrambled DCI on the PDCCH determined by CORSET and USS. In another specific embodiment of these examples, the user receives the second information by: obtaining CORSET and CSS through system messages or preset information, calculating RNTI associated with the first resource used for uplink transmission, and retrieving C-RNTI scrambled DCI on the PDCCH determined by CORSET and CSS.

[0141] In other examples, the second information includes information on DCI format and information indicating whether the grant-free uplink data transmission is successful. In one embodiment of these examples, if the data transmitted by the user includes information indicating that transmission has not completed or information indicating to apply for dedicated resources, or if the base station determines that the user still has data to transmission according to comparison between the buffer status reported by the user and received data volume, then the second information further includes information on resource assigned to the user for subsequent transmission and / or other information required for subsequent transmission, for example, MCS, transmission power control, etc. In another embodiment of these examples, if the user is not in connected state and the transmission data includes information bits applying for access, then the second information further includes timing advance (TA) information and other information required for access of the user. In another embodiment of these examples, with respect to a user with data in grant-free transmission being successfully received by the base station, the second information further includes a data bit identifying identity information of a non-access user, wherein, the identity information is the identity information of the user performing grant-free transmission targeted by the second information. In another embodiment of these examples, the second information may further include information indicating channel state quality; for example, the base station may directly feedback the channel state quality estimated by the base station according to the received data in the second information or only feedback level information indicating high, medium, or low of the channel state.

[0142] In other examples, the method for determining whether the uplink transmission is successful by the user includes: when the user has completed initial access and is in a connected state, if the user receives a second message, and the second message is C-RNTI scrambled DCI, considering the uplink transmission to be successful; otherwise, unsuccessful; when the user has not yet completed initial access, if the user receives a second message, and the received second message is DCI scrambled by RNTI associated with the first resource used for the uplink transmission, and the DCI includes a data bit identifying the identity information of the non-access user, then considering the uplink transmission to be successful, otherwise, unsuccessful.

[0143] In other examples, with respect to a user who succeeds in grant-free transmission and has data for a new transmission, the second resource is a resource required for the user to transmit new data, and is directly given by the second information or obtained through the second information; with respect to a user who fails in grant-free transmission, the second resource is an uplink transmission resource required for performing a grant-free transmission again; the second information may provide reference information for selecting the second resource. In an implementation, the new transmission may be either grant-free transmission or grant-based transmission.

[0144] In other examples, if the data transmitted by the user includes information indicating that transmission has not completed or information indicating to apply for dedicated resources, or if the base station determines that the user still has data to transmit according to comparison between the buffer status reported by the user and received data volume, then the method for determining the second resource associated with the new transmission by the user is: when the user has completed initial access and is in a connected state, if the second information detected within window time is C-RNTI scrambled DCI, the acquired second resource being directly given by the second information; when the user has not yet completed initial access, if the second information detected within the window time is DCI scrambled by RNTI associated with the first resource used for uplink transmission, and the DCI includes a data bit identifying the identity information of the non-access user, the acquired second resource being directly provided by the second information.

[0145] FIG. 7 shows a flow chart of a method 700 for determining a second resource related to a new transmission by a user according to embodiments of the present disclosure.

[0146] As shown in FIG. 7, the method 700 includes steps below:

[0147] Step 701: indicating, by the UE, in the uplink transmission data, a resource that needs to be assigned to the UE;

[0148] Step 702: receiving, by the UE, the second information;

[0149] Step 703: obtaining, by the UE, the second resource according to the second information. For example, the second information includes indication information or configuration information about the resource; and the UE determines the second resource according to the resource indication information or the configuration information in the second resource.

[0150] In an implementation, the new transmission may be either grant-free transmission or grant-based transmission.

[0151] In other examples, the plurality of resource sets have different non-orthogonal multiplex degrees; and the non-orthogonal multiplex degrees may be given by the first information or be calculated through information given by the first information. The method for determining the second resource associated with retransmission by the user is: if the second information detected by the user within the time window is DCI scrambled by RNTI associated with the first resource used for the uplink transmission, the DCI includes information indicating that the transmission is unsuccessful and includes information indicating channel quality (e.g., CSI, or channel quality level: high, medium, or low), then determining, by the user, that the base station has detected use of the first resource for grant-free transmission, but has not received the transmission data correctly, and then, determining, by the user, the second resource according to the channel state quality indicated in the second information.

[0152] In a specific embodiment of these examples, if the second information includes information indicating high channel quality, then the user determines it has high probability that first resource collides, and the second resource is randomly selected from a resource set with a higher non-orthogonal multiplex degree than the first resource set, to reduce probability of first resource collision. In a specific embodiment of these examples, if the second information includes information indicating medium channel quality, then the user determines that first resource collision may have occurred, but the channel quality is not sufficient to support resources with a higher non-orthogonal multiplex degree, then the second resource of the user is randomly selected from a resource set with a non-orthogonal multiplex degree equal to or close to the resources in the first resource set. In a specific embodiment of these examples, if the second information includes information indicating low channel quality, then the user determines that decoding failure may be caused by poor channel quality, and the second resource of the user is randomly selected from a resource set with a lower non-orthogonal multiplex degree than the first resource set, to reduce inter-user interference caused by non-orthogonal resources. FIG. 8 shows a flow chart of a method 800 for determining a second resource related to a retransmission by a user according to embodiments of the present disclosure. As shown in FIG. 8, the method 800 includes steps below:

[0153] Step 801: receiving, by the UE, the second information scrambled by RNTI associated with the first resource;

[0154] Step 802: determining, by the UE, the channel quality information level indicated by the second information. For example, the channel quality information level may be "good", "poor", "medium", or "high", "medium", "low"; or the channel quality information level may also be numerical values such as 1, 2, 3. Or, the channel quality information level may be divided into different ranges, for example, range 1, range 2, range 3, and so on. For convenience of description, description is provided by taking the channel quality information level as one of "high", "medium", "low".

[0155] With respect to different levels of channel quality information, the UE performs different operations as follows:

[0156] If the level is "poor", performing step 803: using, by the UE, a resource set with a lower non-orthogonal multiplex degree;

[0157] If the level is "good", performing step 804: using, by the UE, a resource set with a higher non-orthogonal multiplex degree;

[0158] If the level is "medium", performing step 805: using, by the UE, a resource set with a non-orthogonal multiplex degree equal to or close to the first resource set.

[0159] It may be understood that the above description is only an example, and the UE may also use values of channel quality information or other information related to channel quality to select the resource set to be used.

[0160] In other examples, the plurality of resource sets have different non-orthogonal multiplex degrees; and the non-orthogonal multiplex degrees may be given by the first information or be calculated through information given by the first information. The method for determining the second resource associated with retransmission by the user is: if the user has not received the second information, considering, by the user, that the base station has not detected that the first resource used by the user to perform grant-free uplink transmission is being used by the user, and determining that the channel state is too poor; randomly selecting the second resource from a resource set with a lower non-orthogonal multiplex degree than the first resource set, to compensate for impact of poor channel quality.

[0161] FIG. 9 shows a flow chart of a method 900 for determining a second resource related to a retransmission by a user who has not received the second information according to embodiments of the present disclosure. As shown in FIG. 9, the method 900 includes steps below:

[0162] Step 901: determining, by the UE, that the second information has not been received;

[0163] Step 902: selecting, by the UE, a resource set with a lower non-orthogonal multiplex degree than the non-orthogonal multiplex degree of the first resource set.

[0164] In other examples, the plurality of resource sets have different non-orthogonal multiplex degrees; and the non-orthogonal multiplex degrees may be given by the first information or be calculated through information given by the first information. The method for determining the second resource associated with retransmission by the user is: if the user has not yet completed initial access, the second information detected within the time window is DCI scrambled by RNTI associated with the first resource used to perform uplink transmission, the second information includes the user identity information, but the user identity information is inconsistent with that of the user, then determining, by the user, that collision of first resource has occurred, there is a user selecting the same first resource to perform uplink transmission, and the base station decodes the transmission data of the colliding user, then, selecting the second resource of the user from a resource set with a non-orthogonal multiplex degree not less than the first resource set, for example, randomly selecting from a resource set with a non-orthogonal multiplex degree equal to or close to the first resource set.

[0165] FIG. 10 shows a flow chart of a method 1000 for determining a second resource related to a retransmission by a non-access user according to embodiments of the present disclosure. As shown in FIG. 10, the method 1000 includes steps below:

[0166] Step 1001: receiving, by the UE, the second information, and determining that the identity information in the second information is inconsistent with the identity information of the UE;

[0167] Step 1002: selecting, by the UE, a resource set with a non-orthogonal multiplex degree equal to or close to the non-orthogonal multiplex degree of the first resource set.

[0168] In other examples, if the user undergoes any one of situations below: the resource used in the previous transmission is an orthogonal resource but transmission is unsuccessful, the number of unsuccessful grant-free transmissions exceeds a certain threshold, and a duration of grant-free transmission without acknowledgment of successful transmission exceeds a certain threshold, then the user will fall back to the grant-based transmission mechanism, and the second resource of the user will be obtained in a grant-based mode.

[0169] FIG. 11 shows a simple block diagram of a hardware structure of a user equipment UE 1100 according to embodiments of the present disclosure. The UE 1100 shown in FIG. 11 may be used to implement any method performed by the UE or the user according to the principles of the present disclosure.

[0170] Referring to FIG. 11, the UE 1100 according to the embodiment of the present disclosure includes a transceiver 1101 and a controller 1102. Optionally, the UE 1100 may further include a memory (not shown). The transceiver 1101 may transmit signals or data, or receive signals or data. The controller 1102 may be coupled with the transceiver 1101 and the memory, and control operations of the transceiver 1101 and the memory. The memory has a computer executable instruction stored thereon; and when the instruction is executed by the controller 1102, at least one method corresponding to the above-described respective embodiments of the present disclosure is performed.

[0171] FIG. 12 shows a simple block diagram of a hardware structure of a base station 1200 according to embodiments of the present disclosure. The base station 1200 shown in FIG. 12 may be used to implement any method performed by the base station or a network node according to the principles of the present disclosure.

[0172] Referring to FIG. 12, the base station 1200 according to embodiment of the present disclosure includes a transceiver 1201 and a controller 202. Optionally, the second node 1200 may further include a memory (not shown). The transceiver 1201 may transmit signals or data, or receive signals or data. The controller 1202 may be coupled with the transceiver 1201 and the memory, and control operations of the transceiver 1201 and the memory. The memory has a computer executable instruction stored thereon; and when the instruction is executed by the controller 1202, at least one method corresponding to the above-described respective embodiments of the present disclosure is performed.

[0173] The above merely are exemplary embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modification, equivalent substitution, improvement, and the like, made within the spirit and principles of the present disclosure should be covered within the protection scope of the present disclosure.

[0174] Those skilled in the art may understand that, the present disclosure includes one or more devices for executing the operations in the present disclosure. These devices may be specially designed and fabricated for required purposes, or may also include those known devices in general purpose computers. These devices have computer programs stored therein; and these computer programs are selectively activated or reconfigured. Such a computer program may be stored in a device (e.g., a computer) readable medium or stored in any type of medium suitable for storing electronic instructions and respectively coupled to a bus; the computer readable medium includes, but is not limited to, any type of disk (including a floppy disk, a hard disk, an optical disk, a CD-ROM, and a magneto-optical disk), a Read-Only Memory (ROM), a Random Access Memory (RAM), an Erasable Programmable Read-Only Memory (EPROM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a flash memory, a magnetic card or an optical card. That is, a readable medium includes any medium that stores or transmits information in a form that may be read by a device (e.g., a computer).

[0175] Those skilled in the art may understand that, computer program instructions may be used to implement each block of these structural diagrams and / or block diagrams and / or flow diagrams, and combinations of blocks in these structural diagrams and / or block diagrams and / or flow diagrams. Those skilled in the art may understand that, these computer program instructions may be provided to a general-purpose computer, a professional computer or a processor of other programmable data processing methods to implement, so that solutions specified in a block or a plurality of blocks of the structural diagrams and / or block diagrams and / or flow diagrams disclosed by the present disclosure may be executed by a processor of a computer or other programmable data processing method.

[0176] Those skilled in the art may understand that, steps, measures, and schemes in the various operations, methods, and processes that have been discussed in the present disclosure may be alternated, modified, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and processes already discussed in the present disclosure may also be alternated, modified, rearranged, decomposed, combined, or deleted. Further, steps, measures, and schemes in the various operations, methods, and processes disclosed in the present disclosure may also be alternated, modified, rearranged, decomposed, combined, or deleted in the prior art.

[0177] The above is only a partial implementation of the present disclosure. It should be pointed out that for those ordinarily skilled in the art, several improvements and embellishments may be made without departing from the principles of the present disclosure. These improvements and embellishments should also be considered as the scope of protection of the present disclosure.

Claims

1.A method performed by a user equipment (UE) in a communication system, the method comprising:receiving first information including information related to a plurality of resource sets;performing a first grant-free transmission based on a first resource included in a first resource set among the plurality of resource sets; andin case that second information in response to the first grant-free transmission is received and the first grant-free transmission is unsuccessful, determining a second resource used for a retransmission based on the second information, and performing the retransmission based on the second resource, wherein the second resource is included in a second resource set among configured resource sets.2.The method according to claim 1, further comprising:in case that the second information is not received, determining that the first grant-free transmission is unsuccessful, and performing the retransmission based on a third resource;wherein, the third resource is included in a resource set that is different from the first resource set among the configured resource sets, and a first parameter of the resource set in which the third resource is included is smaller than a first parameter of the first resource set, andwherein the first parameter indicates a ratio of a number of non-orthogonal UEs that are available to support resources in the resource set to a number of orthogonal UEs that are available to support the resources in the resource set.3.The method according to claim 1, wherein the second information includes at least one of: information indicating whether the first grant-free transmission is successful, timing advance information, UE identity information, and channel state information (CSI) related information, andwherein:the second resource is determined from the configured resource set, based on the CSI related information; or,a first parameter of the second resource set in which the second resource is included is not smaller than the first parameter of the first resource set, andwherein the first parameter indicates a ratio of a number of non-orthogonal UEs that are available to support resources in the resource set to a number of orthogonal UEs that are available to support the resources in the resource set.4.The method according to claim 3, wherein:whether the first grant-free transmission is successful is determined based on the information comprised in the second information that indicates whether the first grant-free transmission is successful; or,in case that the UE identity information included in the second information is inconsistent with the identity information of the UE, determining that the first grant-free transmission is unsuccessful.5.The method according to claim 3, wherein, the CSI related information includes at least one of level information of the CSI or a value of the CSI.6.The method according to claim 1, wherein the second information includes at least one of resource information used for a new transmission or configuration parameter information corresponding to the new transmission; andwherein the method further comprises: in case that the first grant-free transmission is successful, performing a new transmission based on the second information.7.The method according to claim 1, wherein the first resource set is determined from the plurality of resource sets based on at least one of followings:random selection;a resource set with a largest first parameter among the plurality of resource sets;determining the CSI level based on the CSI related information for the UE, and determining the first parameter corresponding to the determined CSI level based on a corresponding relationship between the CSI level and the first parameter;determining the first resource set based on a first parameter corresponding to a resource set to which resources of a previous grant-free transmission of the UE belongs; ordetermining the first resource set according to redundancy corresponding to each resource set among the plurality of resource sets determined based on a buffer status of the UE;wherein the first parameter indicates a ratio of a number of non-orthogonal UEs that are available to support resources in the resource set to a number of orthogonal UEs that are available to support the resources in the resource set.8.The method according to claim 1, wherein the configured resource sets are a plurality of resource sets determined based on the first information, or a plurality of resource sets determined based on most recently received first information.9.The method according to claim 1, wherein the first grant-free transmission includes at least one of: information indicating whether the transmission is completed, information related to the buffer status of the UE, information indicating whether to apply for dedicated resources, information identifying UE identity, or information indicating whether to apply for access.10.The method according to claim 1, wherein the first information includes configuration information of the plurality of resource sets,wherein the configuration information includes: at least one of time domain resource information, frequency domain resource information, or multiple access resource information of each resource set among the plurality of resource sets, andwherein:a configuration parameter related to grant-free transmission corresponding to each resource set is comprised in the first information; orthe configuration parameter related to grant-free transmission corresponding to each resource set is preset.11.The method according to claim 10, further comprising:receiving third information including a configuration parameter related to grant-free transmission corresponding to each resource set.12.The method according to claim 10, wherein the configuration parameter related to grant-free transmission includes at least one of modulation and coding scheme (MCS) or transmission power control parameters.13.A method performed by a base station in a communication system, comprising:transmitting first information including information related to a plurality of resource sets;receiving a first grant-free transmission based on a first resource included in a first resource set among the plurality of resource sets;transmitting second information in response to the first grant-free transmission; andin case that the first grant-free transmission is unsuccessful, receiving a retransmission based on a second resource associated with the second information, wherein the second resource is included in a second resource set among the configured resource sets.14.A user equipment (UE) in a communication system, the UE comprising:a transceiver; anda processor coupled with the transceiver and configured to:receive first information including information related to a plurality of resource sets;perform a first grant-free transmission based on a first resource included in a first resource set among the plurality of resource sets; andin case that second information in response to the first grant-free transmission is received and the first grant-free transmission is unsuccessful, determine a second resource used for a retransmission based on the second information, and perform the retransmission based on the second resource, wherein the second resource is included in a second resource set among configured resource sets.15.A base station in a communication system, the base station comprising:a transceiver; anda processor coupled with the transceiver and configured to:transmit first information including information related to a plurality of resource sets;receive a first grant-free transmission based on a first resource included in a first resource set among the plurality of resource sets;transmit second information in response to the first grant-free transmission; andin case that the first grant-free transmission is unsuccessful, receive a retransmission based on a second resource associated with the second information, wherein the second resource is included in a second resource set among the configured resource sets.

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